參數資料
型號: DSP56858E
廠商: 飛思卡爾半導體(中國)有限公司
英文描述: 16-bit Digital Signal Controllers
中文描述: 16位數字信號控制器
文件頁數: 28/64頁
文件大?。?/td> 956K
代理商: DSP56858E
56858 Technical Data, Rev. 6
28
Freescale Semiconductor
Figure 4-5
shows the definitions of the following signal states:
Active state, when a bus or signal is driven, and enters a low impedance state
Tri-stated, when a bus or signal is placed in a high impedance state
Data Valid state, when a signal level has reached V
OL
or V
OH
Data Invalid state, when a signal level is in transition between V
OL
and V
OH
Figure 4-5 Signal States
4.5 External Clock Operation
The 56858 system clock can be derived from a crystal or an external system clock signal. To generate a
reference frequency using the internal oscillator, a reference crystal must be connected between the
EXTAL and XTAL pins.
4.5.1
Crystal Oscillator
The internal oscillator is designed to interface with a parallel-resonant crystal resonator in the frequency
range specified for the external crystal in
Table 4-6
.
In
Figure 4-6
a typical crystal oscillator circuit is
shown. Follow the crystal supplier’s recommendations when selecting a crystal, because crystal
parameters determine the component values required to provide maximum stability and reliable start-up.
The crystal and associated components should be mounted as close as possible to the EXTAL and XTAL
pins to minimize output distortion and start-up stabilization time.
Figure 4-6 Crystal Oscillator
Data Invalid State
Data1
Data2 Valid
Data
Tri-stated
Data3 Valid
Data2
Data3
Data1 Valid
Data Active
Data Active
Sample External Crystal Parameters:
R
z
= 10M
Ω
TOD_SEL bit in CGM must be set to 0
f
c
= 4MHz
Crystal Frequency = 2–4MHz (optimized for 4MHz)
EXTAL XTAL
R
z
f
C
相關PDF資料
PDF描述
DSP56858FV120 16-bit Digital Signal Controllers
DSP56858FVE 16-bit Digital Signal Controllers
DSP56858VF120 16-bit Digital Signal Controllers
DSP5685XEVMUM Feature Phone Software Application Product Brief
DSP5685XUM Feature Phone Software Application Product Brief
相關代理商/技術參數
參數描述
DSP56858EVM 制造商:Freescale Semiconductor 功能描述:Microprocessor Support IC For Use With:D
DSP56858EVMUM_D 制造商:未知廠家 制造商全稱:未知廠家 功能描述:DSP56858 Evaluation Module User's Manual
DSP56858FV120 功能描述:數字信號處理器和控制器 - DSP, DSC 120Mhz/120MIPS RoHS:否 制造商:Microchip Technology 核心:dsPIC 數據總線寬度:16 bit 程序存儲器大小:16 KB 數據 RAM 大小:2 KB 最大時鐘頻率:40 MHz 可編程輸入/輸出端數量:35 定時器數量:3 設備每秒兆指令數:50 MIPs 工作電源電壓:3.3 V 最大工作溫度:+ 85 C 封裝 / 箱體:TQFP-44 安裝風格:SMD/SMT
DSP56858FVE 功能描述:數字信號處理器和控制器 - DSP, DSC 120Mhz/120MIPS RoHS:否 制造商:Microchip Technology 核心:dsPIC 數據總線寬度:16 bit 程序存儲器大小:16 KB 數據 RAM 大小:2 KB 最大時鐘頻率:40 MHz 可編程輸入/輸出端數量:35 定時器數量:3 設備每秒兆指令數:50 MIPs 工作電源電壓:3.3 V 最大工作溫度:+ 85 C 封裝 / 箱體:TQFP-44 安裝風格:SMD/SMT
DSP56858PB_D 制造商:未知廠家 制造商全稱:未知廠家 功能描述:56858 Digital Signal Processor Product Brief